The discussion below is merely provided for general background information and is not intended to be used as an aid in determining the scope of the claimed subject matter.
Servo-hydraulic actuated testing systems are often used to dynamically test elastomer materials and components. Servo-hydraulic actuation provides a high power prime mover which accommodates high velocity and high force input motion. A requirement for many elastomer tests is a high frequency motion excitation. These frequencies can be as high as 1000 Hz or more which is needed to study the response of the material or component used for isolating mechanical vibrations. Testing at these high frequencies creates a very difficult design requirement on the mechanical structure of the testing frame. FIG. 1 is a schematic representation of mechanical vibration resonance where the vibration resonance is illustrated by a crosshead 5 at the top of a testing machine 6 that appears to be leaning with respect to a base 7. The top of the crosshead 5 vibrates the most with the portions below the top experiencing vibration but at a lesser degree as represented by the various patterns thereon. However, it is important to note this is one type of modeled vibration resonance and should not considered limiting. For instance, the base 7 of the testing machine 6 can also experience vibration resonance. In most cases, mechanical resonant modes in a testing frame 8 (base 7, cross-head 5, support columns 9, etc.) define the maximum allowable frequency for a particular testing frame 8 since the resonant modes disrupt the measurements.